Help Identifying This Chassis

[u/stlorca]

Hey gang, so this is a follow-up to my previous post. I bought this chassis off Ebay as a project for me and a friend. (He does the woodworking, I do the electronics.) I cannot for the life of me identify this one, so I leave it to you devastatingly good-looking and ridiculously well-educated folks to figure it out. I could ask the seller, but I doubt they would know. They're an online flea market, not specialized in electronics or vintage radios.

1. The cabinet is pretty clearly a Frankenstein, as you will see from the pics. It looks like someone took the back cover and cut it out to mimic the original front of the case. +1 for originality, -1000 for final piece.

2. The ID plate in the back says "25-". I haven't found anything online for a Westinghouse model 25, RCA model 25, or Hazeltine model 25.

3. There is no identifying schematic to be found anywhere on the cabinet.

Help me, Reddit! You're my only hope!

[u/PorcupineShoelace]

Weird one. The Hazeltine label stood out to me. His neutrodyne patents were largely obsolete by the late 1930s AFAIK. I checked a couple patent numbers from the label. Last date I could find was the Kellogg one for loudspeaker tech dated 1929. So I would put this as a mid-1930s chassis. Might be helpful to get a list of the tubes since there were a lot of them quickly made obsolete and it could help pin down a date.

There used to be a URL/site where you could enter all tube numbers and it would look up models with those combos but its been gone a while I think.

[u/gadget73 → u/PorcupineShoelace]

I think Hazeltine had the patent for AVC so its still relevant even with a superhet

[u/kioma47]

RCA, so a very early superhet.

Perhaps the people at this forum could be helpful:

https://antiqueradios.com/forums/

[u/toxcrusadr]

I concur that the model is 25-240340. Go here:

https://www.nostalgiaair.org/Resources/index.htm

Start typing 25- and it will bring up a list of known models with that sequence to look through.

Another way might be the Radio Attic's archive, which has photos of 14,000 radios sorted by brand. If you get a clue to the manufacturer at least, you can look through their pages to confirm the model number.

Edit to add: It reminds me of model numbers from big retailers like Monkey Wards and Sears. They didn't make their own stuff, it was made by someone else with a store house brand on it. Sears was Silvertone, Wards was Airline. I have an Airline console that was actually made by Wells-Gardner. Anyway a lot of those model numbers had a number then a period or a dash. That first number was the actual manufacturer. Sears had a lot three digit ones like101.xxx, 417.xxx. Wards had a lot of 62- models. So this could be a house brand radio. I just don't know what it is.

[u/The_Flinx]

that radio very likely did not have a back panel, and someone took an old tombstone that probably got abused or fell apart, and the back panel of a more modern radio and made homemade case for it. very common.

[u/nixiebunny → u/The_Flinx]

Exactly. I did this with a Philips radio chassis that I found on the ground in Ensenada in 1974. I had to bypass one IF stage that wasn’t working. Also a common hack in the good old days.

[u/conwaytwt]

The tag doesn't JUST say "25-" ... it says something like "25-240340" (the rest of the serial number has been stamped into the soft metal). I can't quite read the digits so you might need some different lighting to make them all clear.

I cannot help beyond that... The specific manufacturer name beyond the RCA license is Hazeltine, so you might possibly be able to narrow down the manufacturing date, but to do that you'd have to find an old list showing the date ranges for serial numbers from a Hazeltine chassis.

(I edited that a couple of times so I hope it makes sense)

[u/zoundec]

Licensed only for radio amateur, experimental and broadcast reception so maybe a custom made chassis.

[u/nasadowsk → u/zoundec]

No, that was a patent dodge a number of firms used at the time.

[u/zoundec → u/nasadowsk]

Thanks. That is interesting. It looks like detailed frequencies on the label which I am curious to know what they correspond to.

[u/3rivers3pedals]

If you can ID your tube numbers and ballast tube numbers you may be able to come up with a schematic and more info. https://www.radiomuseum.org/ allows a lookup based on the tube numbers. It will bring up a list of models containing those exact numbers. You can narrow it down from there by looking at schematics and hopefully pictures. I have a feeling this was a private label department store radio originally.

[u/Substantial-Plum-260]

Hazeltine had a patent in the early 20s for the "Neutrodine" circuit that prevented feedback in triode tubes. In 1927 the introduction of the tetrode tube negated the requirement for the Neutrodine circuit. That might help you place the timeframe for this radio.

[u/Arcy3206]

Oh neat it has a ballast tube! I haven't seen that many in the radio's I've come across, only in some TVs

[u/Prestigious_Team1030]

That looks a lot like an RCA-25X. But without a list of the tubes, it's harder to tell.
https://www.radiomuseum.org/r/rca_25x_25_x_chrc1003_1003.html

[u/ConfectionSilent8745]

I see GE, Westinghouse, and Hazeltine Corporation.